JURP is a peer-reviewed, online journal devoted to archiving research conducted by undergraduate students in physics and related fields.
October 3, 2011
Determination of a Correlation of Sunspot Number and 20.1 MHz Solar Radio Bursts
There are many phenomena about the Sun that scientists have yet to fully understand. Some of these questions involve the sun’s magnetic field, sunspots, solar flares, and solar radio bursts. We know that due to differential rotation the magnetic fields get tangled and twisted resulting in sunspots. It is theorized that solar radio bursts are a result of solar flares accelerating charged particles in the magnetic field. These accelerated particles emit a wide variety of frequencies. Using a two dipole antenna and a Radio JOVE receiver kit, we obtained over two years of solar burst data at 20.1 MHz. Using these data, a graph was created comparing the visual sunspot number and 20.1 MHz solar burst data. Comparing this to 10.7 cm solar flux data, which is a result of the synchrotron mechanism, the cyclic nature seems identical. We then plotted the sunspot number versus 20.1 MHz radio bursts and found the coefficient of correlation to be 0.65. From this experimental result as well as the theory, we show that there is a relationship between sunspots and solar radio bursts.
Sun, sunspots, magnetic fields, radio bursts
September 7, 2011
Method for Extracting the Frequency Response of an Audio System from a Recording
The ability to compare the technical performance of audio systems is necessary to choose the microphone system that best meets operational requirements. A common method to evaluate a system’s performance is to generate a transfer function for the system and determine the frequency response. Normally this is done by connecting the system to a network analyzer, however not all systems have this ability. This paper outlines procedures developed to non-traditionally measure the frequency response of audio systems using recorded data files.
Acoustics, frequency response, audio signals, evaluating and comparing audio systems